This application claims the priority of German application 196 34 511.1, the disclosure of which is expressly incorporated by reference herein.
The present invention relates to a movable roof construction for an open passenger car, i.e. convertible, having a forward, dimensionally stable roof part and a rearward dimensionally stable roof part. The rearward roof part is swivellable between a closed operative position and an open inoperative position. The forward roof part is displaceable by way of a double-sided parallelogram linkage between a closed operative position and an opened inoperative position. The linkage has a rearward parallelogram control arm arranged on each side of the open passenger car as a fixed component of the rearward roof part, and the forward roof part is fixable by way of a locking device on a windshield cross member of the vehicle body.
DE 44 45 580 C1 describes a roof construction in which the convertible has a forward, dimensionally stable roof shell as well as a rearward, dimensionally stable roof shell in which a rear window is integrated. A parallelogram linkage has one parallelogram control arm fixedly connected on each vehicle side with the rearward roof shell, so that the rearward roof shell is lowered into a storage space in the rear area of the convertible. Simultaneously, the forward roof shell is displaced in parallel toward the rear such that it is lowered onto the rearward roof shell. The roof construction is therefore folded together in its lowered inoperative position in the storage space. In the closed operative position, the two roof shells form a closed coupe roof, the forward roof shell being fixed by a locking device on a windshield cross member of the vehicle body above a windshield. Particularly at higher driving speeds, unpleasant wind noises may occur in the area of the bordering between the forward roof shell and the rearward roof shell.
It is an object of the present invention to provide a roof construction in which wind noises are reliably prevented, particularly at higher driving speeds.
This object has been achieved in accordance with the present invention by providing a locking mechanism between two parallelogram control arms on each side of the parallelogram linkage. The locking mechanism is coupled in a controlled manner by transmission devices on the locking device of the forward roof part on the windshield cross member such that the locking mechanism can be unlocked for a release of the parallelogram control arms together with an unlocking of the locking device.
The foregoing solution according to the present invention was based on the recognition that the wind noises in the area of the bordering between the forward and the rearward roof part arise because of a gap which occurs at high driving speeds as a result of the forming vacuum. The solution according to the present invention prevents, in the closed operative position of the roof construction, any relative movement between the two parallelogram control arms on each side of the parallelogram linkage. Thereby a gap formation and thus also the occurrence of wind noises are reliably avoided.
Because the locking mechanism on each side of the parallelogram linkage in a particularly advantageous manner by way of corresponding transmission devices is coupled in a controlled fashion directly with the locking device of the forward roof part on the windshield cross member, no separate drive is required for operating the locking mechanism. The locking mechanism is coupled by the transmission devices such with the respective unlocking or locking operations of the locking device that an unlocking of the locking device automatically also ensures an unlocking of the locking mechanism. Inversely, a locking of the locking device automatically causes a locking of the adjacent parallelogram control arms by the locking mechanism.
As transmission devices between the locking device and the locking mechanism situated away therefrom, either tension devices or pressure devices or combined tension/pressure devices can be provided. Correspondingly designed Bowden cables can be provided as tension, pressure or combined tension/pressure devices.
According to yet another feature of the present invention, a locking pin can be assigned to the one parallelogram control arm as well as a catch which is longitudinally displaceable on the other parallelogram control arm and which, by way of a hook extension in the locked condition, reaches behind the locking pin and constitute as the locking mechanism between the two parallelogram control arms. This is a particularly simple and nevertheless operationally reliable further development.
A still further feature of the present invention is a cable pull, which is coupled to the locking device of the forward roof part, serving as a transmission device for each locking catch. A restoring spring is assigned to each locking catch which loads the locking catch in the locking direction. The cable pull is therefore used as a pure tension device which couples the locking catch for the opening movement, that is, the unlocking movement, to the locking device of the forward roof part. The restoring spring causes the automatic restoring of the locking catch into its locking position as soon as the locking catch is no longer loaded by the cable pull in the opening direction. The restoring of the locking catch is an exclusive function of the spring force of the restoring spring so that, even if corresponding hydraulic or electrohydraulic movement drives for the roof construction fail, a locking of the locking mechanism will still be ensured.
Yet another advantageous feature of the present invention involves the locking pin configured as an eccentric member which, in different relative positions with respect to the parallelogram control arm provided with the locking catch, can be fixed to the adjacent parallelogram control arm. As a result, the locking catch and the locking pin, in the locked condition, independently of spacing tolerances between the parallelogram control arms, are ensured in every case to be in contact with one another under tension.
A further aspect of the present invention is a receiving contour of the hook extension, which reaches behind the eccentric locking pen. The configuration of the contour is such that an essentially point contact with the eccentric locking pin takes place. Thereby, a blocking of the locking mechanism and a throwing-out of the locking in the contact area are prevented.
A nose-shaped exterior side of the hook extension is provided, in accordance with the present invention, with a stop bevel for automatic reaching behind the eccentric. This permits an automatic locking of the locking mechanism in the case of an emergency operation. That is, the stop bevel on the locking catch against the restoring force of the restoring spring during the closing of the roof construction is pushed away in the opening direction and behind the eccentric is automatically restored into the locking position by the restoring spring.